Oakville Veterinary Surgery, Station Road, Lawley Bank, Telford TF4 2LP

Christmas Toxins

Christmas Toxins

It’s still only mid-December, but already we’ve seen loads of pets suffering from poisoning, usually from
human holiday treats! While we can usually treat these if we see them early enough, it isn’t a nice
process for your pet (or us, or you…). In this blog, we’re going to look at some of the more common
poisonings we see at this time of year, and summarise the treatment options available.

Chocolate
Well known for being poisonous to dogs, but equally toxic to cats (although they are less likely to
consume!). The active ingredient is theobromine, a chemical stimulant related to caffeine (which is also
toxic!).
The effects start with restlessness and progress to vomiting and diarrhoea, muscle tremors, abnormal
heartbeats, and potentially seizures and death.
The initial treatment (if symptoms have not yet appeared) is to induce vomiting. We use a drug called
apomorphine in dogs, and one called xylazine in cats, to make them feel sick, and then vomit up their
stomach contents. This is a fast acting drug – usually within a few minutes – but is quite unpleasant, and
apomorphine especially makes dogs feel really miserable and unhappy (one of the side effects,
technically called “dysphoria”). Sometimes, we may use a drug called activated charcoal to absorb any
toxin remaining in the intestinal tract as well.
If symptoms have developed, then the standard treatment is to be admitted for observations,
hospitalisation, and intravenous fluids. By this point, the toxin has already been absorbed, so inducing
vomiting isn’t usually appropriate, While hospitalised, we can manage each symptom as it occurs – for
example, anti-emetic drugs for the vomiting, anticonvulsants for tremors or seizures, and a wide range of
heart drugs to control the abnormal heartbeats.

Vine-fruits (e.g. raisins, currants, sultanas)
Found in Christmas Cake, Christmas Pudding and Mince Pies, as well as snack selections and other
festive delights, some (but not all!) dried fruit contains a component that causes severe kidney failure.
Unfortunately, the exact chemical(s) involved aren’t yet known; in addition, there is no way to tell which
raisins, currants or grapes contain toxic levels of the compound. Some dogs may have eaten the fruit for
years with no ill-effects (leading their owners to assume that they’re safe), and then collapse and die
after a handful of raisins that had a higher level of the toxic ingredient.
The symptoms usually kick in about 6-12 hours after consumption, and include vomiting, lethargy, loss of
appetite, dehydration, increased thirst, and tremors. In most cases, urine production will abruptly stop
or slow down, and the dog will go into full-blown kidney failure within 72 hours – which is usually fatal.
If the dog has just eaten some raisins, we would again induce vomiting. However, if a large quantity were
eaten, we weren’t able to get them all back (!), or it’s more than a couple of hours since consumption,
then we’d usually admit them for intensive care. This involves hospitalisation, high dose intravenous fluid
therapy (to flush the kidneys through) and drugs to manage the symptoms.

Lilies
Many plants from the Lily family have a similar effect on cats that raisins do on dogs, leading to acute
kidney injury; the difference is that ALL cats are equally susceptible, and can even be affected by the
pollen. Lily poisoning is usually fatal, but if we respond in time, we can sometimes maintain some kidney
function with very aggressive inpatient treatment.

Nuts
Most nuts will cause at most a messy stomach upset (vomiting and diarrhoea – not what you want at
Christmas!); however, in some situations they can be more dangerous. Salted nuts can be, and are,
eaten in high enough quantities to lead to salt poisoning. This causes severe thirst, then water is drawn
out of the brain, leading to seizures, collapse, coma and death. Salt poisoning can usually be managed
again by intensive care nursing, although if neurological signs (e.g. tremors, dullness, wobbliness) occur
before treatment starts, the prognosis is quite poor.
Macadamia nuts are particularly unpleasant for dogs, causing weakness, lethargy, vomiting, wobbliness,
muscle tremors, and sometimes an abnormally high body temperature and internal organ damage.
Fortunately, with supportive care, they are usually non-fatal – just nasty!

“Sugar-Free” bakes or sweets
Sugar-free sweets, bakes, gum, and other treats often contain the artificial sweetener xylitol. While
harmless to humans (and cats), this can cause a catastrophic drop in a dog’s blood sugar levels, causing
severe hypoglycaemia. This usually occurs within a few hours (even as little as 30 minutes) and leads to
vomiting, weakness, wobbliness, depression, collapse, seizures, a coma and then death. Emergency first
aid is to apply honey or glucogel to the gums (to raise the blood sugar) and then get them in to us ASAP!
Even if they survive the hypo, some dogs will go into liver failure a few days later, especially if they’ve
eaten a lot, so it’s really important to monitor them closely – best done in the clinic, where we can
monitor their blood sugar and liver enzymes as needed.

Prevention is better than cure – so keep your pets away from potential poisons if at all possible! If they
have been exposed, you should contact us immediately.